Intermittent-grip device for hoisting mechanism.



R. 1. NICCOY.

INTEBMITTENT GRIP DEVICE FOR HOISTING MECHANISM.

APPLICATION FILED mha. |913. nENEwED MAR.4,1915.

THE NoRR/s PETERS CO.. PHOTG-LITHO.. WASHINGTON, D, CA

R. 1. IVIcCUY.

INTERMITTENT GRIP DEVICE FOR HOISTING MECHANISNI.

APPLICATION FILED IAN. 3, I9I3 RENEWED MAR. 4| |915- Patented May 25, 1915 2 SHEETS-SHEET 2.

71. @V w a .f 2/ A S A l a 7 2 f THE NORRIS PETERS co, PHON f 'TH-1 'vAH/NHTON, D

-4 sfrafrns ROBERT J. MCCOY, OF FRT SMITH, ARKANSAS, ASSIGNB OF ONE-HALF TO WILLIAM., M. CRAVENS, OF FORT SMITH, ARKANSAS.

mrERMrTTnNr-Gmr nnvr'cnron Hoisrrne MnoHANisM.

1,140,519. l Application filed January 3, 1913, Serial No.

T0 all whom it may concern Be it known that I, ROBERT J. MCCOY, a citizen of the United States, residing at Fort Smith, in the county of Sebastian and State of Arkansas, have invented new and usefulv :improvements in lntermittent-Grip Devices for Hoisting Mechanism, of which the following is a specification.

This invention is an improved hoisting machine for raising andl lowering heavy weights, for pulling stumps and for doing other work of this class, the invention consisting in the construction, combination and arrangement of devices hereinafter described and claimed.y

rlhe object of this invention is to provide an improved hoisting machine which may be readily operated, which may be readily movedv from place to place and by means of which heavy weights may be raised or lowered, stumps may be pulled and otherlike work may be performed by a single operator. v

In the accompanying drawings :-Figure 1 is a side elevation of a hoisting machine constructed in accordance with my invention. Fig. 2 is a plan of the same. Fig. 3 is a horizontal sectional view of the same on the plane indicated by the line ca -a of Fig. 1. Fig. l is a detail vertical sectional view of the same on the plane indicated by the line b-b of Fig. 1.

In the form of the invention here shown, a carrying 'frame 1 is provided, which is horizontally arranged and provided at its ends with supporting legs 2.

A pair of standards 3 rise vertically from the frame 1 at a point substantially midway between its ends and at one end of the said frame is a vertical frame or standard 4f which is provided near its upper and lower ends with pairs of pulleys 5-6.

A drum 7 has its axle shaft mounted in bearings near the lower ends of the standards 3.

A master sprocket wheel 8 is connected to the axle shaft of the drum for rotation therewith and on opposite sides of the said sprocket wheels are ratchet wheels 9-10 which are also secured to the drum shaft for rotation therewith and the respective ratchet teeth of which incline in opposite directions or are reversely arranged. spring pressed pawl 11 is provided for engagement with the ratchet wheel and a simi- Specification of Letters Patent.

` Fatented May 25, 1915.

740,043. Renewed March 4, 1915. Serial No. 12,175.

lar pawl 12 is provided for engagement with the ratchet wheel 10.

Cords 13-14 are respectively connected to the said pawls, the cord 13 passing around a direction pulley 15 and its outer end being connected to a key 16, the cord 14: being connected to a key 17. The said frame 1 has openings or sockets in which the said keys are placed and the keys may be turned and frictionally held in said sockets and employed to disengage their respective pawls from the respective ratchet wheels.

A lever 18 comprises a yoke portion 19 and av handle 2O which extends from one end of the yoke portion. The latter is pivotallyA mounted at a point intermediate its ends on a pivot 20 which connects the standards 3.

A spur gear 21 is mounted on the pivot 20 and onvopposite sides oi' the said spur gear and connected thereto for rotation therewith are ratchet wheels 22-23, which are respectively above the ratchet wheels 9-10 and are reversely arranged, so that the ratchet wheel 22 is reversely arranged with respect to the ratchet wheel 9 and the ratchet wheel 23 is reversely arranged with respect to the ratchet wheel 10.

In opposite ends of the yoke portion 19 of the lever 18 are 'spur gears 24-25 which engage opposite sides of the gear 21 and are mounted for rotation and also for oscillating movement with the lever 18, the axles of the said gears being respectively indicatedy at 26*27. Y y

A sprocket wheel 28 is secured to one side of the spur gear 24C for rotation therewith and a sprocket wheel 29 is similarly related to the gear 25.

An endless sprocket chain 30 engages the under side of the master sprocket wheel 8 and the upper sides of the sprocket wheels 28-29 so that the said sprocket wheels are connected together by the sprocket chains.

the pulleys 5-6 as shown and may be connected by a suitable hook or other device to a weight to be hoisted orlowered or to a stump to be pulled.

When it is desired to raise a weight or pull a stump to which the hoisting rope has thus been attached, the pawl 11 is permitted to engage the ratchet wheel 9, the pawl 31 is permitted to engage the ratchet wheel 22 and the pawls 12-32 are respectively disengaged from the ratchet wheels 10-23.

VWhen the lever is operated, each upward stroke thereof causes the pawl 31 to rotate the ratchet wheel 22 and, hence also the spur gear so that the spur gears which are engaged therewith also rotate the sprocket wheels carried by the lever and cause said sprocket wheels to move the sprocket chain 30 and cause said sprocket chain to partly turn the master sprocket wheel 8 in the required direction to cause the drum to wind up the hoisting rope, reverse rotation of said master sprocket wheel 8 being prevented by the engagement of the pawl l1 with the ratchet wheel 9. VAt each downstroke of the lever, the master wheel 8 is held by the engagement of the pawl 11 with the ratchet wheel 9, the pawl 31 slipping on the ratchet wheel'22.

By reversing the arrangement of the pawls, the operation of the lever causes the drum to turn by a step-by-step movement in the reverse direction so as to unwind the hoisting rope and, hence, permit a weight to be lowered by the machine.

While I have herein shown and described a preferred form of the invention, I would have it understood that lchanges may be made in the form, proportion and construction of the several parts without departing from the spirit of the invention and within the scope of the appended claims.

' I claim l. In a machine of the class described,

Copies of this patent may be obtained for ve cents each, by addressing the the combination of a master sprocket wheel arranged to be connected to a rotary driven element for vrotation therewith, a ratchet wheel alsoY arranged to be connected to the drivenV element, a pawl to engage the ratchet wheel, and an oscillating lever, a gear concentric with the pivot of the lever, a ratchet wheel fast to said gear, a pawl carried by the lever to engage said ratchet wheel, sprocket wheels mounted on the lever, gears mounted on the lever and engaging opposite sides of the first-named gear, and an endless sprocket chain connecting the said sprocket wheels.

2. In a machine of the class described, the

combination of a master gear arranged to be connected to a rotary driven element for rotation therewith, a pair of reversely arranged ratchet wheels for rotating with said master gear and driven element, pawls for engagement respectively with said reversely arranged ratchet wheels, a, lever mounted for oscillation, a spur gear concentric with the pivot of said lever, reversely arranged ratchet wheels also concentric with the pivots of the lever and connected to said spur gear for rotation therewith, pawls carried by the lever for engagement respectively.

with the last mentioned ratchet wheels, spur gears mounted on the lever for rotation and Y also for oscillation by the lever and engaged with opposite sides of the first-mentioned Y spur gear, sprocket wheels also mounted on the lever and respectively connected to the oscillatory spur gears yfor rotation therewith, and an endless sprocket chainconnecting the sprocket wheels.

n testimony whereof I affix my signature in presence of two witnesses.

ROBERT J. MCCOY.

'Washingtoln D. C.

Commissioner; of Patents, Y i 

